The advent of virtualization technologies for computing resources has provided benefits with respect to managing large-scale computing resources for many customers with diverse needs and has allowed various computing resources or computing services to be efficiently and securely shared by multiple customers. For example, virtualization technologies may allow a single physical computing machine to be shared among multiple customers by providing each customer with one or more computing instances hosted by the single physical computing machine (physical host) using a hypervisor. Each computing instance may be a guest machine acting as a distinct logical computing system that provides a customer with the perception that the customer is the sole operator and administrator of a given virtualized hardware computing resource.
When launching a computing instance, a public network address and a private network address may be assigned to the computing instance. The public network address may be reachable over a public network (e.g., the Internet) and may be used for network communications with computers and computing services outside of a computing service environment (e.g., a cloud environment or a virtual private environment). The private network address may be used for routing network communications between computing instances within the same private network, but the private network address may not be reachable over a public network and may not be used to communicate with computing services outside of a computing service environment. When the computing instance is stopped or terminated, the private network address may be disassociated from the computing instance. If the computing instance is restarted, a new private network address may be assigned to the restarted computing instance.